qos: Register irq notify after adding the qos request

Before adding the irq affinity based qos request to the list, if
the affinity of the interrupt changes it will trigger notify call.
This notifier call will try to update the qos request. Accessing
the qos request which is not yet added to the list leads to a
NULL pointer exception.

Avoid this race by registering the notifier after adding the
qos request.

Change-Id: I99869cc233573b5db10e4f3224d65c29511050ea
Signed-off-by: Anil Kumar Mamidala <amami@codeaurora.org>
This commit is contained in:
Anil Kumar Mamidala 2016-04-22 12:42:51 +05:30 committed by Gerrit - the friendly Code Review server
parent d0fd03a2cf
commit 9879d0300b

View file

@ -596,7 +596,6 @@ void pm_qos_add_request(struct pm_qos_request *req,
#ifdef CONFIG_SMP
case PM_QOS_REQ_AFFINE_IRQ:
if (irq_can_set_affinity(req->irq)) {
int ret = 0;
struct irq_desc *desc = irq_to_desc(req->irq);
struct cpumask *mask = desc->irq_data.common->affinity;
@ -606,13 +605,6 @@ void pm_qos_add_request(struct pm_qos_request *req,
req->irq_notify.notify = pm_qos_irq_notify;
req->irq_notify.release = pm_qos_irq_release;
ret = irq_set_affinity_notifier(req->irq,
&req->irq_notify);
if (ret) {
WARN(1, KERN_ERR "IRQ affinity notify set failed\n");
req->type = PM_QOS_REQ_ALL_CORES;
cpumask_setall(&req->cpus_affine);
}
} else {
req->type = PM_QOS_REQ_ALL_CORES;
cpumask_setall(&req->cpus_affine);
@ -634,6 +626,24 @@ void pm_qos_add_request(struct pm_qos_request *req,
trace_pm_qos_add_request(pm_qos_class, value);
pm_qos_update_target(pm_qos_array[pm_qos_class]->constraints,
req, PM_QOS_ADD_REQ, value);
#ifdef CONFIG_SMP
if (req->type == PM_QOS_REQ_AFFINE_IRQ &&
irq_can_set_affinity(req->irq)) {
int ret = 0;
ret = irq_set_affinity_notifier(req->irq,
&req->irq_notify);
if (ret) {
WARN(1, "IRQ affinity notify set failed\n");
req->type = PM_QOS_REQ_ALL_CORES;
cpumask_setall(&req->cpus_affine);
pm_qos_update_target(
pm_qos_array[pm_qos_class]->constraints,
req, PM_QOS_UPDATE_REQ, value);
}
}
#endif
}
EXPORT_SYMBOL_GPL(pm_qos_add_request);